Amido-thiolphosphoric acid -o,s-dimethyl ester

ABSTRACT

O-alkyl-S-methyl-phosphoric acid diester amides, which possess biocidal, especially insecticidal and acaricidal, properties.

United States Patent Schrader et al.

[451 Sept. 5, 1972 54] AMIDO-THIOLPHOSPHORIC ACID 0,S-DIMETHYL ESTERInventors:

Assignee:

Filed:

Appl. No.:

Gerhard Schrader, Wuppertal- Cronenberg; Walter Lorenz,Wuppertal-Vohwinkel; Giinter Unterstenhoier, Opladen; Ingeborg Hammann,Cologne, all of Germany Farbenfabriken Bayer Aktiengesellschaft,Leverkusen, Germany June 30, 1965 Foreign Application Priority Data July2, 1964 US. Cl.

Int. Cl......

Germany; ..F 43 32s ..C07f 9/24, AOln 9/36 Field of Search ..260/959 Melnikov et al., Chem. Abstracts, v01. 50, p. 2,415,

Primary Examiner'.loseph Rebold Assistant Examiner-Anton H. SuttoAttomey-Burgess, Dinklage & Sprung [57] ABSTRACTO-alkyl-S-methyl-phosphoric acid diester amides, which possess biocidal,especially insecticidal and acaricidal, properties.

1 Claim, No Drawings AMIDO-THIOLPHOSPHORIC ACID -O,S- DIMETHYL ESTER Thepresent invention relates to particular amidothiolphosphoric acid estersand to compositions containing the same, as well as to the productionand use thereof.

It is an object of the present invention to provide particularamido-thiolphosphoric acid esters which possess outstanding biocidal,especially insecticidal and acaricidal, properties, as well as acomparatively low toxicity toward warm-blooded animals and a lowphytotoxicity, in particular when compared with analogous knowncompounds.

It is another object of the present invention to provide such acidesters in the form of compositions with carrier vehicles, such asdispersible carrier vehicles used generally for hygiene controlpurposes.

It is still another object of the present invention to provide a processfor the production of such amidothiol-phosphoric acid esters which issmooth and efficient and which leads to significant yields.

It is a further object of the present invention to provide methods ofusing the particular amidothiolphosphoric acid esters of the foregoingtype in a new way for combating pests, especially by applying to suchpests and their habitat biocidally effective amounts of the particularacid esters of the present invention. Other and further objects of thepresent invention will become apparent from a study of the withinspecification and accompanying examples.

It has been found in accordance with the present invention that theparticular amido-thiolphosphoric acid esters of the general formula i-s-oHi HzN (I) in which R is a linear or branched, preferably lower,alkyl radical, such as a C C alkyl radical, including methyl, ethyl,n-propyl, isopropyl, n-butyl, isobutyl, sec.-butyl, tert.-butyl, n-amyl,etc. radicals, yet also contemplating higher alkyl radicals up to atleast about C -C such as octyl, isooctyl, decyl, dodecyl, etc., possessoutstanding biocidal, especially insecticidal and acaricidal,properties.

Furthermore, it has been found that the particular compounds of thepresent invention can be obtained by a smooth and efficient reaction andwith good yields, when amido-O-alkylthiophosphoric acid salts of thegeneral formulas are reacted with methylating agents.

in formulas [la and 11b, R has the same meaning as defined for formulaI, and M represents a monovalent metal equivalent, preferably an alkalimetal atom such as sodium or potassium.

As can be seen from the above formulas the amido- O-alkylthiophosphoricacid salts react in the methylation in the thiol form with constantshift of the equilibrium to that form as the reaction proceeds.

Surprisingly, the particular, new compounds of the present inventionpossess a substantially better insecticidal and acaricidal effectivenessand/or considerably lower toxicity to warm-blooded animals then theclosest known compounds of analogous constitution and similar effect.Thus, the instant compounds represent a very important addition tobiocidal or pest control technology.

The process according to the present invention is preferably carried outin the presence of inert solvents. Water or polar organic solvents, forexample, lower aliphatic alcohols, especially lower alkylols including CC lower alkanols, such as methanol, ethanol, propanol, butanol,pentanol, and the like, lower aliphatic ketones, especially lowerdi-alkyl ketones including diC C alkyl ketones, such as acetone, methylethyl ketone, diethyl ketone, diisopropyl ketone, diisobutyl ketone, andthe like, lower aliphatic nitriles, especially lower alkane nitrilesincluding C,- C alkyl cyanides, such as acetonitrile, propionitrile,butyronitrile, and the like, and mixtures thereof, have proved to besuitable for this purpose.

It is also advantageous, in order to achieve good yields and to obtainpure products, to carry out the reaction at room temperature or at aslightly elevated temperature (preferably at a temperature substantiallybetween about 20 to 30 C) and, after the starting components have beenmixed together, to continue stirring for some time e.g. about it hour),with heating under reflux, if desired.

As methylating agents, methyl halides, such as methyl chloride, methylbromide, methyl iodide and methyl fluoride, dimethyl sulfate and thecorresponding tosylates have been found to be particularly suitable.

In most cases, the compounds of the present invention are obtained inthe form of colorless crystals, some of which are water-soluble, evenwhen cooling the reaction mixture to about 0 C, or after the solvent hasbeen distilled off. The instant compounds have a sharp melting point.For further purification, these compounds can be recrystallized from thecustomary solvents or mixtures of solvents, such as ether, petroleumether or acetonitrile, thus being easily further purified.

The particular amido-thiolphosphoric acid esters according to thepresent invention are distinguished by an excellent insecticidal actiontowards sucking and eating insects, for example, aphids, spider mites,caterpillars and flies. The instant compounds not only possess a verygood contact-insecticidal activity, but also an excellent systemicaction. Their outstanding effectiveness against resistent spider mitesespecially must be emphasized. On the other hand, the new compoundsaccording to the present invention exhibit only a comparatively lowtoxicity against warm-blooded animals, and even possess acorrespondingly comparatively low phytotoxicity.

Because of these desirable properties, the compounds of the presentinvention are usable as pest control agents, particularly in plantprotection and also in the field of general hygiene. The low degree ofmammalian toxicity as compared with the comparatively high degree ofbiocidal activity of the instant compounds renders such compoundsextremely well suited to handling and manipulation in preparingformulations which may be used manually or by automatic equipment forapplying the same to any surface, and especially plants and surroundingsoil, whereby to control and minimize the insect problem as it may occurin a given situation.

The new compounds of the instant invention can be used as pesticideseither alone or in admixture with solid or liquid carriers or diluents.

The active compounds according to the instant invention can be utilized,if desired, in the form of the usual formulations or compositions withdispersible carrier vehicles, such as solutions, emulsions, suspensions,emulsifiable concentrates, spray powders, pastes, soluble powders,dusting agents, granulates, etc. These are prepared in known manner, forinstance by extending the active agents with solvents and/or dispersiblesolid carriers optionally with the use of emulsifying,

agents and/or dispersing agents, whereby, for example, in the case wherewater is used asdiluent, organic solvents may be added as auxiliarysolvents (cf. Agricultural Chemicals, Mar. 1960, pages 35-38). Thefollowing may be chiefly considered for use as carrier vehicles orassistants for this purpose: solvents, such as aromatic hydrocarbons(for instance, benzene, toluene, xylene, etc.), halogenated, especiallychlorinated, aromatic hydrocarbons (for instance, chlorobenzenes),paraffins for instance, petroleum fractions), chlorinated aliphatichydrocarbons (for instance, methylene chloride, etc.), alcohols (forinstance, methanol, ethanol, propanol, butanol, etc.), ethers,ether-alcohols (for instance, glycol monomethyl ether, etc.), amines(for instance, ethanolamine, etc.), amides (for instance, dimethylformamide, etc.), ketones (for instance, acetone, etc.), and water;dispersible finely divided solid carriers, such as natural groundminerals (for instance, kaolins, alumina, silica, chalk, i.e., calciumcarbonate, talc, kieselguhr, etc.), and synthetic ground minerals (forinstance, highly dispersed silicic acid, silicates, e.g., alkalisilicates, etc.); emulsifying agents, such as appreciated and anionicemulsifying agents (for instance, polyethylene oxide esters of fattyacids, polyethylene oxide ethers of fatty alcohols, compositionssulfonates, aryl sulfonates, etc., and especially alkyl aryl-polyglycolethers, magnesium stearate, sodium active etc.); and dispersing agents,such as lignin, sulfite waste liquors, methyl cellulose, etc.

As will be appreciated by the artisan, the active compounds according tothe instant invention may be present in such formulations orcompositions in the form of mixtures with one another and with otherknown active substances, if desired.

The substances according to the invention may be employed by themselvesas the artisan will appreciate, in the form of their compositions withsolid or liquid dispersible carrier vehicles or other known compatibleactive agents, or in the form of particular dosage preparations forspecific application made therefrom,-

such as solutions, emulsions, suspensions, powders, pastes andgranulates, which are thus ready for use.

As concerns commercial preparations, these generally contemplate carriercomposition mixtures in which the active compound is present in anamount substantially between about 0.1-05percent by weight, andpreferably 0.5- percent by weight of the mixture, whereas carriercomposition mixture suitable for direct application or field applicationgenerally contemplate those in which the active compound is present inan amount substantially between about 0.001 and 5 percent by weight ofthe mixture. Thus such mixtures over-all contemplate an amount of theactive compound which is effective for the purpose in question and whichis generally between about 0.001 and percent by weight of the mixture.Thus, the instant formulations or compositions are applied in the usualmanner, for example, by pouring, spraying, atomizing, vaporizing,smoking, i.e. fumigating, scattering, dusting, and the like.

The outstanding insecticidal and acaricidal effectiveness of theparticular compounds according to the present invention, as well astheir superiority to compounds of analogous constitution and similaraction,

such as those which are known from U.S. Patent No.

3,019,250, may be appreciated from the following ex amples demonstratingsuch utility, which examples are given for the purpose of illustrating,while not limiting, the present invention.

EXAMPLE I Plutella Test Solvent: 3 parts by weight acetone Emulsifier: 1part by weight alkyl aryl polyglycol ether For the preparation of asuitable active material preparation, 1 part by weight of the particularactive material is mixed with the stated amount of solvent, whichcontains the stated amount of emulsifier, and the concentrate therebyformed is diluted with water to the desired concentration.

Cabbage leaves Brassica oleracea) are sprayed with the particular activematerial preparation and infested with caterpillars of the cabbagebutterfly (Plutella maculipennis).

After a given period of time, the degree of killing is determinedpercentagewise. percent indicates that all of the caterpillars arekilled, whereas 0 percent indicates that no caterpillars are killed.

The active materials, active material concentrations, evaluation timeand results are given in the following Table l:

TAB LE 1 (Plant'damaging insects) Degree Active material of killingconcentration in percent Active material (constitution) in percent after4 days (A) O NH: 0. 1 100 3 (known from U.S. Patent No. 3,019,250,Example 2) TABLE 1 (unlinucd (Plant-damaging insects) Active material(constitution) (B) O NH:

Cl--CHrSI (known from U.S. Patent No. 3,019,250, Example 3) (III) (EH 0O P- S CH NH; (according to the invention, Example 5) (IV) C2H50 0 P-SCH3 NHz (according to the invention, Example 6) (C) CzHeO 0 -SCHz-S CH3it is seen from Table i that compounds Ill and IV of the presentinvention possess a 66 %percent better effect( i.e. total effectiveness)than the known compound C at 0.1 percent concentration, and while sucheffect of the instant compounds remains at 0.01 percent concen- EXAMPLE2 Myzus test (contact action) D we Active material 0! kil lmzconcentration in percent in percent alter 4 days Solvent: 3 parts byweight acetone Emulsifier: l part by weight alkyl aryl polyglycol etherFor the preparation of a suitable active material preparation, 1 part byweight of the particular active material is mixed with the stated amountof solvent, which contains the stated amount of emulsifier, and theconcentrate thereby formed is diluted with water to the desiredconcentration.

Cabbage plants (Brassica oleracea), which are strongly infested withpeach leaf mice (Myzus persicae), are sprayed drip wet with theparticular active material preparation.

After a given period of time, the degree of killing is determinedpercentagewise. 100 percent indicates that all of the leaf lice arekilled, while 0 percent indicates that no leaf lice are killed.

The active materials, active material concentrations, evaluation timeand results are given in the following Table 2:

TABLE 2 (Plant-damaging insects) Degree of Active materiel killing inconcentration percent after Active material (constitution) in percent 24hours (B) 0 NH: 0. 1 99 ll 0. 01 0 01- CH: S-P\ 0 Calls (Known from US.Patent No. 3,019,250, Example 3) (III') OHIO 0 0. 1 100 ll 0. 01 100 P-S OH; 0. 001

(According to the invention, Example 5) (IV) 011150 0 0. 1 ll 0. 01 100P- S OH:

NHz

(According to the invention, Example 6) men:

Here again, in Table 2 the instant compounds are shown to besignificantly better than the known analogous compound B at lowerconcentrations,

whereby it is clear that the present invention enables marked biocidaleffectiveness to be achieved at lower concentrations of the activecompound than heretofore.

EXAMPLE 3 Rhodalosiphum Test (systemic action) Solvent: 3 parts byweight acetone Emulsifier: 1 part by weight alkyl aryl polyglycol etherFor the preparation of a suitable active material preparation, 1 part byweight of the particular active material is mixed with the stated amountof solvent, which contains the stated amount of emulsifier, and theconcentrate thereby formed is diluted with water to the desiredconcentration.

Oat plants Avena sativa), which are heavily infested with oat lice(Rhopalosiphum padi), have the particular active material preparationpoured over them so that the active material preparation penetrates intothe soil without wetting the leaves of the oat plants. The activematerial is taken up from the soil by the oat plants and thus reachesthe attacked leaves.

After a given period of time, the degree of killing is determinedpercentagewise. 100 percent indicates that all of the leaf lice arekilled, whereas percent indicates that no leaf lice are killed.

The active materials, active material concentrations, evaluation timeand results are given in the following Table 3:

TABLE 3 (Plant-damaging insects) Table 3 clearly establishes the superbtotal effectiveness of the instant compounds, even at the extremely lowconcentration of 0.001 percent, whereas the known compounds only exhibiteffectiveness at the comparatively high concentration of 0.1 percent butnot at a lower concentration.

EXAMPLE 4 Tetranychus Test Solvent: 3 parts by weight acetoneEmulsifier: 1 part by weight alkyl aryl polyglycol ether For thepreparation of a suitable active material preparation, l part by weightof the particular active material is mixed with the stated amount ofsolvent, which contains the stated amount of emulsifier, and theconcentrate thereby formed is diluted with water to the desiredconcentration.

Bean plants (Phaseolus vulgaris), which have a height of about l0-30 cm,are sprayed dripping wet with the particular active materialpreparation. These bean plants are heavily infested with all stages ofdevelopment of the common spider mite Tetranychus urticae).

After a stated period of time, the effectiveness of the particularactive material preparation is determined by counting the dead pests.The degree of killing so obtained is determined percentagewise. percentindicates that all of the spider mites are killed, whereas 0 percentindicates that no spider mites are killed.

The active materials, active material concentrations, evaluation timeand results are given in the following Table 4:

Degree of Active material killing in concentration percent Activematerial (constitution) in percent after 8 days (A) 0 NH: 0.1 100 ll 0.01 0 S-CH2SP OCzHs (Known from U.S. Patent No. 3,019,250, Example 2)(E") (")/NH1 0. 1 20 c1 oms-P 0CzH5 (Known from Us. Patent No.3,019,250, Example 3) (111) CHQO 0 0.1 100 II 0.01 100 P-SCH; 0.001 100NHz (According to the invention, Example 6) CzHsO O 0. 1 100 ll 0. 01100 PSCH3 0.001 100 (According to the invention, Example 6) TABLE 4(Plant-damaging spider mites) Degree of Active material killing inconcentration percent after Active material (constitution) in percent 8days (known from U.S. Patcnt No. 3,019,250, Example 2 TABLE 4 Continued(Plant-damaging spider mites) Active material (constitution) (B"') NH;

ll Cl-- CH3-SP O C H (known from U.S. Patent No. 3,019,250, Example 3)(III) 01130 O ll P-S CH3 NHz (According to the invention, Example 5) z i0 II P =SCH3 NH;

(According to the invention, Example 6) Table 4 also demonstrates themarked superiority of the instant compounds as opposed to analogousknown compounds, in consideration of the consistently high biocidaleffect of the compounds of the invention at lower concentrations, whencompared with the absence of any effect of the known compounds at suchlower concentrations.

The following examples are given for the purpose of illustrating, whilenot limiting, the production process of the present invention:

EXAMPLE 5 I (IIIIIII) 89.4 grams (0.6 mol) of the sodium salt ofamido-O- methyl-thiolphosphoric acid are dissolved in .100 cc. water. 65grams (0.5 mol) dimethyl sulfate are added dropwise to this solution atto C, while stirring. After stirring for a half-hour at roomtemperature, the reaction mixture is treated with a solution ofpotassium carbonate until it becomes turbid and then repeatedly shakenout with methylene chloride. The methylene chloride solution is driedover anhydrous sodium sulfate and the solvent distilled off. Thedistillation residue solidifies in the form of crystals. It isrecrystallized from twenty times its quantity of ether andamidothiolphosphoric acid-O,S-dimethyl-ester is obtained in the form ofcolorless, water-soluble, small needles of melting point 54 C. The yieldis 54 g (76.5 percent of the theoretical).

Analysis: Calculated for molecular weight 141.1

S 2.73% N 9.69% S percent solutions kill percent of the same pest.

Degree of Active material killing in concentration percent after inpercent 8 days EXAMPLE 6 C2Ha \l P- S CH3 grams (0.55 mol) of the sodiumsalt of amido-O- ethyl-thiophosphoric acid are dissolved in [00 ccwater. 65 g( 0.5 mol) dimethyl sulfate are added dropwise to thissolution at 20 to 30 C, with external cooling, and after stirring for ahalf-hour at room temperature, the reaction mixture is mixed with apotassium carbonate solution until cloudiness occurs. The aqueoussolution is then shaken out four times with cc methylene chloride eachtime, the organic phase dried over anhydrous sodium sulfate and thesolvent finally distilled off. The distillation residue is suspended inether, undissolved material is filtered off with suction, andamido-thiolphosphoric acid-O-ethyl-S-methyl ester is obtained in theform of colorless, water-soluble crystals of melting point 70 C. Theyield is 59g (76.1 percent of the theoretical). There is no change ofthe melting point of the compound after recrystallization fromacetonitrile.

Analysis:

Calculated for molecular weight 155.3:

N 9.03% 3 20.66% P 19.97% Found: N 9.15% s 20.88% P 19.70%

Caterpillars and spider mites are completely killed by 0.001 percentsolutions of the compound.

EXAMPLE 7 I1-C3Hy0 O P-S OH:

HzN (V) To a solution of 80 g (0.45 mol) of the sodium salt ofamido-O-n-propylthiolphosphoric acid (m.p. 127 C) in cc water, there areadded dropwise at 25 to 30 C, with external cooling, 50 g (0.4 mol)dimethyl sulfate. The mixture is stirred for a half-hour at roomtemperature, and the reaction product is then salted out with apotassium carbonate solution and worked up in the manner described inthe preceding examples. 46 grams (69.2 percent of the theoretical) ofamidothiolphosphoric acid-O-n-propyl-S-methyl ester are obtained in theform of a light yellow, somewhat viscous oil, which solidifies uponcooling in ice and again liquefies at room temperature.

Analysis:

Calculated for molecular weight 169.1:

N 8.28% S l9.96% P 18.32% Found: N 8.24% S 19.02% P l8.4l%

EXAMPLE 8 isoC:H\f|) P-S CH3 HzN 106 grams (0.6 mol) of the sodium saltof amido-O- isopropyl-thiolphosphoric acid (m.p. 173 C) are dissolved in130 cc water. This solution is mixed dropwise at 25to 30 C, whilecooling, with 65 g (0.5 mol) dimethyl sulfate and, after stirring themixture for a half-hour, the reaction product is salted out with asaturated potassium carbonate solution. It is extracted from the aqueoussolution by repeated shaking with methylene chloride. Finally, theorganic layer is dried over anhydrous sodium sulfate and the solventdistilled off. The residue solidifies; it is suspended in ether andfiltered off with suction. Amido-thiolphosphoric acid-O-isopropyl-S-methyl ester is obtained as a colorless crystalline powderof melting point 6870 C. The yield is 47 g (55 percent of thetheoretical).

Analysis:

Calculated for molecular weight 169.1:

N 8.28% s [8.96% P 18.32% Found: N 8.33% 5 19.42% P 18.16%

EXAMPLE 9 Upon repeating the procedure of Example 4, using correspondingmolar amounts of the sodium salts of amido-O-n-butyl-thiolphosphoricacid, amido-O-isobutyl-thiolphosphoric acid,amido-O-sec.-butylthiolphosphoric acid,amido-O-ter.t.-butylthiolphosphoric acid,amido-O-n-pentyl-thiolphosphoric acid, amido-O-n-octyl-thiolphosphoricacid, and amido-O-n-dodecyl-thiolphosphoric acid, as the case may be,the following products, respectively, will be obtained, each of whichwill possess the desired biocidal, especially insecticidal andacaricidal, properties, as well as a low degree of mammalian toxicityand a low degree of phytotoxicity: amido-thiolphosphoricacid-O-n-butyl-S-methyl ester, amide-thiolphosphoricacid-O-isobutyl-S-methyl ester, amido-thiolphosphoricacid-O-sec.-butyl-S-methyl ester, amidothiolphosphoricacid-O-tert.-butyl-S-methyl ester, amide-thiolphosphoricacid-O-n-pentyl-S-methyl ester, amide-thiolphosphoricacid-O-n-octyl-Smethyl ester,

and amido-thiolphosphoric acid-O-n-dodecyLS-methyl ester.

Accordingly, the present invention contemplates the production ofparticular, new amido-thiolphosphoric acid esters having generalformulaI above, by reacting an amido-O-alkyl-thiophosphoric acid salt ofgeneral formula II above with a methylating agent, whereby thecorresponding amide-thiolphosphoric acid is produced, and especially onehaving the formula lower alky10 O i l s -cn.t

11: (VII) Biocidal, such as pesticidal, and especially insecticidal andacaricidal, compositions are also contemplated in accordance with thepresent invention which include a mixture of a dispersible carriervehicle of the foregoing type, and a biocidally effective amount of anamide-thiolphosphoric acid ester of the foregoing type.

Furthermore, methods of using the instant com pounds are alsocontemplated, including especially a method of combating pests, such asinsects, and/or acarids, by applying to such pest, and especiallyinsects and/or acarids, and their habitat a biocidally, especiallypesticidally, effective amount of the compounds of the instant typeeither alone or in admixture with a dispersible carrier vehicle of theforegoing type in the well known field application or direct applicationproportions.

The foregoing amido-thiolphosphoric acid esters of the present inventionindeed possess a higher degree of potency and activity than presentlyknown analogous biocidal compounds, especially as regards pesticidal,and in particular insecticidal and acaricidal, activity. Because of thehigh potency even at comparatively low concentrations, the instantcompounds may be employed more economically with ease in manipulationand use in the field. Because of the distinctly low toxicity towardwarm-blooded animals and the distinctly low phytotoxicity of thesecompounds, such compounds are especially useful in crop controltechniquesin ridding plant crops of sucking and eating insects. Becauseof their singular properties, the instant compounds have very goodcontact-insecticidal activity as well as excellent systemic action,which renders the same useful as hygiene control agents, in particularcrop control agents.

It will be appreciated that the instant specification and examples areset forth by way of illustration and not limitation, and that variousmodifications and changes may be made without departing from the spiritand scope of the present invention.

What is claimed is:

1. Amide-thiolphosphoric acid-O,S-dimethyl ester having the formula CHaO0 Farben 11 UNL'IED STA"ES PATENT OFFIC CERTIFICATE OF CORRECTION PatentNo) 3,689,604 Dated ept. 5, 1972 Inventor(s) GE CHRADE, w'nzn LORENZ,GUNTER UNTERSTENI-IOFEB 6% MIN It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Col. 3, line 46, cancel "appreciated" and substitute therefor,--non-ionic--; col. 3, lines 48-49, cancel "compositions" and substitutetherefor Y--a1ky1--; col; 3, line 51, cancel "active" and substitutetherefor --o1eate--; col. 4, line 11, change "0.1-05 percent" to"OJ-95%"; col. 5, Table I, Example C,

after the formula insert -(known from U.S. Patent No. 3,019,250, Example20)--; col. 7, Table 3 2nd item under "Active nianerial" heading, change"(13")" to --(B")--; col. 9, Table 4, under Example (IV"'), change "P-SCH to "P-SCH col. 10, Example 6, change "(2 11 0" to -C H 0--; col. 101 nc 32, change "thiophosphoric" to -thoiphosphoric--; col. 12, line 24,change "pest"-to --pests- Signed and sealed this 13th day of March 1973(SEAL) Attest:

EDWARD M.FLETCHER,JR.

Attesting Officer ROBERT GOTTSCI-IALK Commissioner of Patents

